Harish S. Hosalkar

Endoprosthetic reconstructions: Results of long-term followup of 139 patients

Our primary goal in doing this study was to determine the effect of prosthesis location, patient age, periprosthetic infection, and primary versus revision placement on endoprosthetic survival. We also examined our endoprosthetic survival rates and reasons for failure. We retrospectively studied 139 endoprosthetic reconstructions performed between 1984 and 2002, including 57 distal femur, 27 proximal femur, 26 proximal tibia, 17 proximal humerus, 4 distal humerus, 3 total scapula, 3 total femur, and 2 total humerus reconstructions. Location of reconstruction and presence of periprosthetic infection significantly affected endoprosthetic survival. Survival was not affected by patient age or primary versus revision placement. Overall, Kaplan-Meier event-free endoprosthetic survival was 86%, 80%, and 69% at 3, 5, and 10-year followup. The trend for endoprosthetic survival from best to worst was proximal femur, proximal humerus, distal femur, proximal tibia, and distal humerus. Reasons for failure included mechanical failure (eight patients), tumor recurrence (eight patients), aseptic loosening (six patients), dislocation (two patients), periprosthetic infection (two patients), and endoprosthetic malalignment (one patient). Our periprosthetic infection rate was 2.2%. The local recurrence rate in patients treated for primary malignant tumors was 6.8%, similar to previous limb-salvage and amputation studies. Overall, we have found that endoprosthetic reconstruction is a reliable limb-salvage technique. Level of Evidence: Therapeutic study, Level IV-2 (case series). See the Guidelines for Authors for a complete description of levels of evidence.

Feasibility of T2* mapping for the evaluation of hip joint cartilage at 1.5T using a three-dimensional (3D), gradient-echo (GRE) sequence: a prospective study.

This study defines the feasibility of utilizing three‐dimensional (3D) gradient‐echo (GRE) MRI at 1.5T for T  2* mapping to assess hip joint cartilage degenerative changes using standard morphological MR grading while comparing it to delayed gadolinium‐enhanced MRI of cartilage (dGEMRIC). MRI was obtained from 10 asymptomatic young adult volunteers and 33 patients with symptomatic femoroacetabular impingement (FAI). The protocol included T  2* mapping without gadolinium‐enhancement utilizing a 3D‐GRE sequence with six echoes, and after gadolinium injection, routine hip sequences, and a dual‐flip‐angle 3D‐GRE sequence for dGEMRIC T1 mapping. Cartilage was classified as normal, with mild changes, or with severe degenerative changes based on morphological MRI. T1 and T  2* findings were subsequently correlated. There were significant differences between volunteers and patients in normally‐rated cartilage only for T1 values. Both T1 and T  2* values decreased significantly with the various grades of cartilage damage. There was a statistically significant correlation between standard MRI and T  2* (T1) (P < 0.05). High intraclass correlation was noted for both T1 and T  2* . Correlation factor was 0.860 to 0.954 (T  2* ‐T1 intraobserver) and 0.826 to 0.867 (T  2* ‐T1 interobserver). It is feasible to gather further information about cartilage status within the hip joint using GRE T  2* mapping at 1.5T. Magn Reson Med, 2009.

Intralesional curettage for grades II and III giant cell tumors of bone.

Grade III Campanacci lesions are traditionally treated with wide resections based on their postulated aggressiveness and potential for local recurrence and metastasis. The purpose of this study was to determine if there was a difference in local recurrence rates of Grade II and III lesions treated with intralesional curettage, burring, phenol cauterization, and polymethylmethacrylate application. Sixty-three patients (26 Campanacci Grade II and 37 Grade III lesions) met the inclusion criteria. No pathologic fractures, including intraarticular fractures, were included in this study. Followup averaged 108 months (range, 25–259 months). The overall local recurrence rate was 6% (4 of 63 patients), with no observed difference between Grade II and III lesions. The average Musculoskeletal Tumor Society functional score was 27.9/30 (93%). The mean range of motion of the adjacent joint was 97%. Patients with radiographic signs of osteoarthritis before treatment did not show substantial progression, and only one patient developed radiographic signs of degenerative arthritis postoperatively. Our distal metastatic rate was 3.2%. These data support the use of intralesional curettage and burring with adjuvant phenol and polymethylmethacrylate even in Grade III lesions, in the absence of pathologic fracture, regardless of the presence or extent of extraosseous extension. Level of Evidence: Therapeutic study, Level III-1 (retrospective cohort). See the Guidelines for Authors for a complete description of levels of evidence.

Serial arterial embolization for large sacral giant-cell tumors: mid- to long-term results.

Study Design. Level III retrospective case series with historical controls. Objective. To evaluate the mid- to long-term outcomes of serial arterial embolization as a primary treatment modality for large sacral giant-cell tumors (SGCT). Summary of Background Data. Giant-cell tumors are potentially aggressive benign tumors that can cause significant morbidity and may occasionally prove lethal. Large GCTs in the sacrum present a significant challenge, and treatment methods, including surgical resection and radiation, are associated with morbid complications and high recurrence rates. This report presents the mid- to long-term follow-up results of our cases of SGCT treated with serial arterial embolization. Methods. Nine consecutive patients with biopsy-proven SGCTs received initial primary treatment with serial arterial embolization between 1984 and 2006. All patients underwent angiography and selective arterial embolization at the time of diagnosis, followed by repeat embolization every 6 weeks until no new vessels were noted, and then at 6 and 18 months following stabilization of the lesion. Patients were closely monitored with MRI and/or CT every 6 months for 5 years and annually thereafter. Functional outcomes were measured using the 1993 Musculoskeletal Tumor Society Rating Scale (MSTS93). Results. The mean duration of follow-up in this series was 8.96 years (median, 7.8 years; range, 3.8–21.2 years). No progression was noted in 7 of the 9 cases. Two cases experienced tumor progression of less than 1 cm early in the treatment course and continued to remain asymptomatic. Adjuvant radiation therapy provided local control in 1 of these cases, while radiation and chemotherapy failed in the other case with ultimate mortality. All patients demonstrated substantial pain relief. Cross-sectional MSTS93 scores were obtained in the 8 surviving patients at their most recent follow-up visit with a mean score of 29/30. Conclusions. Serial arterial embolization is a useful primary treatment modality for large SGCTs given the favorable long-term results and potential morbidity of alternative treatments.

Occipitalization of the atlas in children. Morphologic classification, associations, and clinical relevance.

BACKGROUND Occipitalization is defined as a congenital fusion of the atlas to the base of the occiput. We are not aware of any previous studies addressing the morphologic patterns of occipitalization or the implications of occipitalization in children. We present data on what we believe is the largest reported series of children with occipitalization studied with computed tomography and/or magnetic resonance imaging, and we provide a description of their clinical characteristics. METHODS We retrospectively reviewed all cases of occipitalization in children included in our spine database. Patient charts and imaging studies were reviewed. A new morphologic classification of occipitalization was developed from the two-dimensional sagittal and coronal reformatted computed tomographic reconstructions and/or magnetic resonance images. The classification includes four patterns according to the anatomic site of occipitalization (Zones 1, 2, and 3 and a combination of those zones), and it was applied to this group of patients. Imaging studies were also reviewed for evidence of cervical instability and for other anomalies of the craniovertebral junction. RESULTS Thirty patients with occipitalization were identified. There were twenty-four boys and six girls with a mean age of 6.5 years. The morphologic categorization was Zone 1 (a fused anterior arch) in six patients, Zone 2 (fused lateral masses) in five, Zone 3 (a fused posterior arch) in four, and a combination of fused zones in fifteen. Seventeen patients (57%) had atlantoaxial instability, and eight of them had an associated C2-C3 fusion. Eleven patients (37%) had spinal canal encroachment, and five of them had clinical findings of myelopathy. The highest prevalence of spinal canal encroachment (63%) was noted in patients with occipitalization in Zone 2. CONCLUSIONS Occipitalization is associated with abnormalities that lead to narrowing of the space available for the spinal cord or brainstem. The risk of atlantoaxial instability developing is particularly high when there is an associated congenital C2-C3 fusion. Two-dimensional sagittal and coronal reformatted computed tomographic reconstructions and/or magnetic resonance images can help to establish the diagnosis and permit categorization of occipitalization in three zones, each of which may have a different prognostic implication.

Child abuse and orthopaedic injury patterns: analysis at a level I pediatric trauma center.

Background Child abuse is a serious threat to the physical and psychosocial well-being of the pediatric population. Musculoskeletal injuries are common manifestations of child abuse. There have been multiple studies that have attempted to identify the factors associated with, and the specific injury patterns seen with musculoskeletal trauma from child abuse, yet there have been no large studies that have used prospectively collected data and controlled comparisons. The purpose of our study was to describe the patterns of orthopaedic injury for child abuse cases detected in the large urban area that our institution serves, and to compare the injury profiles of these victims of child abuse to that of general (accidental) trauma patients seen in the emergency room and/or hospitalized during the same time period. Methods This study is a retrospective review of prospectively collected information from an urban level I pediatric trauma center. Five hundred cases of child abuse (age birth to 48 mo) were identified by membership in our institutions Suspected Child Abuse and Neglect database collected between 1998 and 2007. These cases were compared against 985 general trauma (accidental) control patients of the same age group from 2000 to 2003. Age, sex, and injury type were compared. Results Victims of child abuse were on average younger than accidental trauma patients in the cohort of patients under 48 months of age. There was no difference in sex distribution between child abuse and accidental trauma patients. When the entire cohort of patients under 48 months were examined after adjusting for age and sex, the odds of rib (14.4 times), tibia/fibula (6.3 times), radius/ulna (5.8 times), and clavicle fractures (4.4 times) were significantly higher in child abuse versus accidental trauma patients. When regrouping the data based on age, in patients younger than 18 months of age, the odds of rib (23.7 times), tibia/fibula (12.8 times), humerus (2.3 times), and femur fractures (1.8 times) were found to be significantly higher in the child abuse group. Yet, in the more than 18 months age group, the risk of humerus (3.4 times) and femur fractures (3.3 times) was actually higher in the accidental trauma group than in the child abuse group. Conclusions Patients who present to an urban level I pediatric trauma center and are victims of abuse are generally younger, and have an equal propensity to be male or female. It is important for the clinician to recognize that the age of the patient (younger or older than 18 mo and/or walking age) is an important determinant in identifying injury patterns suspicious for abuse. Patients below the age of 18 months who present with rib, tibia/fibula, humerus, or femur fractures are more likely to be victims of abuse than accidental trauma patients. Yet, when patients advance in age beyond 18 months, their presentation with long bone fractures (ie, femur and humerus) is more likely to be related to accidental trauma than child abuse. Level of Evidence level III, prognostic study.

T2∗ mapping of hip joint cartilage in various histological grades of degeneration

OBJECTIVE To evaluate T2* values in various histological severities of osteoarthritis (OA). METHOD Magnetic resonance imaging (MRI) and T2* mapping including a three-dimensional (3D) double-echo steady-state (DESS) sequence for morphological cartilage assessment and a 3D multiecho data image combination (MEDIC) sequence for T2* mapping were conducted in 21 human femoral head specimens with varying severities of OA. Subsequently, histological assessment was undertaken in all specimens to correlate the observations of T2* mapping with histological analyses. According to the Mankin score, four grades of histological changes were determined: grade 0 (Mankin scores of 0-4), grade I (scores of 5-8), grade II (scores of 9-10), and grade III (scores of 11-14). For reliability assessment, cartilage T2* measurements were repeated after 4 weeks in 10 randomly selected femoral head specimens. RESULTS T2* values decreased significantly with increasing cartilage degeneration (total P-values <0.001) ranging from 36.3 ± 4.3 ms in grade 0 regions to 22.8 ± 4.3 ms in regions with grade III changes. Pearson correlation analysis proved a fair correlation between T2* values and Mankin score (correlation coefficient = -0.362) that was statistically significant (P-value <0.001). Intra-class correlation (ICC) analysis demonstrated high intra-observer reproducibility for the T2* measurement (ICC: 0.949, P < 0.001). CONCLUSIONS Given the advantages of the T2* mapping technique with no need for contrast medium, high image resolution and ability to perform 3D biochemically sensitive imaging, T2* mapping may be a strong addition to the currently evolving era of cartilage biochemical imaging.

The diagnostic accuracy of MRI versus CT imaging for osteoid osteoma in children.

Advanced imaging often is obtained in children suspected of having osteoid osteoma. We hypothesized that magnetic resonance imaging gives a falsely aggressive appearance and that computed tomography is better for identifying osteoid osteoma. This is the first prospective blinded study comparatively assessing these imaging studies in children. Twelve preoperative magnetic resonance imaging scans of confirmed cases of osteoid osteoma were collected. Three radiologists blinded to the diagnosis reviewed these images. Only a clinical history of skeletal pain was given. Lesions were classified as benign-latent, benign-aggressive, or malignant. Radiologists were asked to list their primary diagnosis (with a confidence level from 1–10). Seven of these 12 children also had computed tomography scans that subsequently were reviewed in similar manner. With computed tomography scans, lesions were accurately identified as benign-latent (15/21 readings, 71%) and as osteoid osteoma (14/21 readings) more frequently than with magnetic resonance imaging scans (7/36 readings, 19%). Level of Evidence: Diagnostic study, Level III-1 (study of nonconsecutive patients—no consistently applied reference gold standard). See the Guidelines for Authors for a complete description of levels of evidence.

Reproducibility of dGEMRIC in assessment of hip joint cartilage: a prospective study

To investigate the reproducibility of dGEMRIC in the assessment of cartilage health of the adult asymptomatic hip joint.

Medial epicondyle fractures in the pediatric population.

Humeral medial epicondyle fractures in the pediatric population account for up to 20% of elbow fractures, 60% of which are associated with elbow dislocation. Isolated injuries can occur from either direct trauma or avulsion. Medial epicondyle fractures also occur in combination with elbow dislocations. Traditional management by cast immobilization increasingly is being replaced with early fixation and mobilization. Relative indications for surgical fixation include ulnar nerve entrapment, gross elbow instability, and fractures in athletic or other patients who require high‐demand upper extremity function. Absolute indications for surgical intervention are an incarcerated fragment in the joint or open fractures. Radiographic assessment of these injuries and their true degree of displacement remain controversial.